Zilch's AK Design Collaborative - Econowave Speaker
- Thread starter Zilch
- Start date
man.. ya'll need to quit calling JBL cause all you're doing is pissing them off, and I'll never get my guides at this rate
What makes you think I will continue to call them? Did you read what I posted? I contacted them last week and essentually was told to check back and I did so.
I am very upset about this situation and do not appreciate what you are implying.
similost
Rockin and Rollin....
I'm just give you crap.. Not being serious.. I'm still calling them myself, just a little frustrated that I'm jumping on the band wagon so late and it's harder to get parts from JBL now because everyone else is trying to... At least I'm trying to get ones that aren't as in demand with all these new builds..
rage
Well-Known Member
JBL and QSC are both being good to us.
When I spoke with JBL I asked them if they get a lot of these calls, which seemed to be the case.
I suppose some people are just more patient on the phone than others.
Personally, I have very good luck and got my waveguides on the first phone call! I too was late to the party, so do not despair guys!
When I spoke with JBL I asked them if they get a lot of these calls, which seemed to be the case.
I suppose some people are just more patient on the phone than others.
Personally, I have very good luck and got my waveguides on the first phone call! I too was late to the party, so do not despair guys!
\
No problem man. Just misunderstood.
I am going to start my cabs this weekend and most likely will have them ready in one day, sans finishing. Maybe just make another baffle for the Daytons. I understand that JBL doesn't have to sell these so I will just wait till they are available.
skywave-rider
Slumming in Akihabara
Round #5:
Top to bottom: Max (5:00), 3, 1, 11, 9, 7, Min (Off).
Yeah, +/- 1.5 dB @ 1:00, yellow.
I'll build it final tomorrow.... :yes:
Looks great. I'm curious to see what you ended up with for x-o point and whether or not you are treating the top end of woofer response with anything.
:thmbsp:
Excellent findings.
We sure seem to have the VHF knocked. :thmbsp:
I'll say it again for those new to this: neither JBL nor QSC sells these waveguides as components; we are relying upon their good will to make their inventory of repair parts normally dedicated to servicing factory repair centers available to us directly. Waveguides do not typically break, and the popularity of these projects represents a significant and largely unanticipated demand for these items.
I have spoken with Dave at JBL Pro Parts about this on several prior occasions; perhaps it's time I do that again to see if some sort of alternative "arrangement" might be appropriate.
I am not aware that QSC makes the waveguide we're using in a 1.5" throat variant.
As shown, 1420 Hz, though that moves around somewhat with the varying attenuation as the HF rolloff marches up and down the LF curve, which you can see (cyan) when the HF is turned off. I aimed for that dip, as I cannot seem to get rid of it. I would not be surprised to discover that it is somewhat mitigated when I round over the woofer recess, which at 11" equates to 1.233 kHz.
Two major findings:
1) The highpass must be moved down when using the QSC waveguide with either DE250 or D220Ti.
2) DC300 must be "tamed," and it does not sound as good up close to 2 kHz.
I am doing this the hard way, and once phase and vertical lobing enter into the mix, it becomes very hard, indeed; it'll be interesting to see what crossover optimization software might suggest.... :yes:
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rage
Well-Known Member
My el-cheapo measuring setup ran $140 total.
Behringer ECM8000 mic $50
ART USB Dual Pre $80 - has mic preamp, phantom power and USB connction plus gain controls and balanced outputs in a 1/4" format. I have not had any luck getting the sound out of the unit but the input side works fine.
jdft is the free RTA software I'm using for windows. it seems idiot proof enough, at least so much that I can use it. very little configuring involved.
Its really cool to center the mic about listening position, have the RTA on the big TV and toe the speakers in and move them around. I can watch the upper frequencies smooth out as I toe the speakers in.
I'm picking Keggers brain on smoothing the LF section out some so we'll see what can be accomplished there.
I've also read Waynes crossover document about 3 times now and its starting to click.
Behringer ECM8000 mic $50
ART USB Dual Pre $80 - has mic preamp, phantom power and USB connction plus gain controls and balanced outputs in a 1/4" format. I have not had any luck getting the sound out of the unit but the input side works fine.
jdft is the free RTA software I'm using for windows. it seems idiot proof enough, at least so much that I can use it. very little configuring involved.
Its really cool to center the mic about listening position, have the RTA on the big TV and toe the speakers in and move them around. I can watch the upper frequencies smooth out as I toe the speakers in.
I'm picking Keggers brain on smoothing the LF section out some so we'll see what can be accomplished there.
I've also read Waynes crossover document about 3 times now and its starting to click.
Be careful concluding anything measuring both speakers concurrently unless you are certain the noise source is uncorrelated; otherwise the mic must be at the absolute acoustic center between them for the result to be valid.
Play both and move the mic left to right to see this in the VHF response. It must be dead on within +/- 1/16" horizontally, and you can easily find the center between them this way.... :yes:
Play both and move the mic left to right to see this in the VHF response. It must be dead on within +/- 1/16" horizontally, and you can easily find the center between them this way.... :yes:
zog666
Active Member
Thanks! first time I've had a bash at this, so been very interesting, though I had a lot of help and advice from good mate Col who's been making sound systems for a while.
I had the MDF cut to order at a precision MDF cutting place,
25mm front baffle, the other sides 18mm MDF.
internal volume is 120 litres.
very simple paint job using 2 coats of pavement paint
currently powering them with a TDA8920 Class D amp module.
Excellent, thanks for that, this will give me some brainfood to chew on over the Xmas hols.. I made it with the crossovers outside the cabinets so I can get at them easily when I have a go at applying this.
As Homer Simpson said... "Doh!" - well all a good fun learning experience!Footnote: One of your early schematics had the highpass inductor to common before the series cap. Not surprising that didn't work....
Round #5 DE250/QSC/DC300 update with preliminary schematic here, so it's all in one place:
http://www.audiokarma.org/forums/showthread.php?p=3296114#post3296114
Edit: Added lowpass filter measurement detail 12/24.
http://www.audiokarma.org/forums/showthread.php?p=3296114#post3296114
Edit: Added lowpass filter measurement detail 12/24.
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donprice
Wound up workin' at a gas station....
Would you say you like the sound of the DE250/QSC combo better than the standard ewave?
Are the HF and LF sections of crossover "independent" enough that they can be used separately? The DC300 certainly fits the bill for the econo woofer and I was curious if this LF section would mate up with the standard eWave for a complete off the shelf design in the PE trapezoidal cabs.
Regarding the JBL horns, it would really be nice if someone at PE could get them stocked and save the JBL folks the trouble of dealing with small orders. Or we could wait for Pyle to clone them....:scratch2:
WiredGuy'll have to tell you, or you can come by for a listen. Don't know when, but I'll go on to complete a pair; they're clearly an "upgrade."
Only if I'm lucky. I'll be posting a bit more data on "managing" the DC300 later today.
That's my intention, a complete eWave "kit" using the PE Trap enclosure, which is why I haven't made new baffles like Jack did to front mount the woofer with QSC. Next, I'll be swapping in a D220Ti driver to bring it back to "Econo" with the big waveguide, then JBL waveguides (including a different one) with the DC300 front mounted.
[I'm taking a holiday break to hack into another pair of AR4x with the 8" waveguide first, tho.... :tongue: ]
O.K., so much for the break:
http://www.jblproservice.com/pdf/AE Series Compact Models/AC1895-WH.pdf
Attachments
Bauhausler
Rational Subjectivist
O.K., so much for the break:
http://www.jblproservice.com/pdf/AE Series Compact Models/AC1895-WH.pdf
I have a whole mess of AR4s laying around in various states of deadness. What woofer do you use?
That's JBL 228H from AC18 (93 dB, 250W, SFG, copper-clad pole piece, 2.5" edgewound VC,) which wants to be vented (there's room for a pair of 1.5" ports on the front baffle), but Geddes would say I am slam-dunk done -- merely add subwoofers (his products use high-efficiency woofers closed-box). I'll try some others on hand, but the real purpose here is to analyze the 8" waveguide as eWave candidate. It has D2500Ti on it right now, and I have data to post using that later today. D220Ti will fit, but just barely, due to the depth of the waveguide in this box. I'll try them both, two of each, for now.
Installing the waveguide is straightforward like the standard one as shown in your large Advent tutorial: cut the hole. I recall you being stunned by the simplicity of that upgrade; this one's all but the same. In this instance, I have removed the stock input terminal screws and run the driver leads out those two holes for experimental crossover connections and measurements. The flange of the 8" waveguide covers the remains of the stock AR4x tweeter recess, whereas the 6" requires some patch and fill to mount on center.
Woofers on hand for closed-box are EPI, AR, JBL, KLH, Boston, and others, but I need to order some Daytons toward a turnkey solution like Skywave has built. Also want to try the 120° version of this waveguide.... :yes:
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Bauhausler
Rational Subjectivist
I should really be leaving this ewave stuff alone for my own good. I'm up to the elbows - to the point of working on Christmas - in urgent projects. I think I have a pic of the chip amp I'm working on for a Make Magazine feature.
But the speakers stuff still appeals more than any other projects. Probably the ease of the build, as yo usaid. I've spent my afternoon hand-wiring tiny chips and switches. It's like doing hernia operations on sparrows.
Found the pix...
Squelette the Bare Bones Amplifier:
